Development of Automated Fire Suppression Technology to Respond to Obstructed Fire Suppression Scenarios on Naval Ships
Development of Automated Fire Suppression Technology to Respond to Obstructed Fire Suppression Scenarios on Naval Ships
▲ Research Specialist Park Jin-ouk, Department of Fire Safety Research, KICT
Prologue
The autonomous rapid initial fire suppression system is a novel concept of a fire suppression system for efficient fire response in large-scale hangar spaces, such as aircraft hangars on naval ships or cargo loading areas on civilian vessels. It can quickly detect fires in their early stages using high-performance detectors, and autonomously aim and discharge extinguishing water at the seat of the fire to suppress or prevent large-scale fires from occurring. This autonomous rapid initial fire suppression system was successfully developed through the "Development of Autonomous Rapid Initial Fire Suppression System" project (June 2019 to May 2022), supported by the Ministry of Trade, Industry and Energy (MOTIE) and the Defense Acquisition Program Administration (DAPA), in response to the need for enhanced fire safety on ships and reduced operational manpower (cost savings). However, the developed autonomous rapid initial fire suppression system is limited to responding to general fires through rapid water discharge for initial fires. It has limitations in addressing the obstructed fire suppression scenarios that frequently occur on ships, posing various risks. Therefore, a follow-up study on the practical implementation and technological advancement of the autonomous fire suppression system for responding to Obstructed Fire Suppression Scenarios has been initiated.
This article briefly introduces the autonomous rapid initial fire suppression system for obstructed fire suppression scenarios on naval vessels and the procedure for validating its fire suppression performance. The "Development of Autonomous Suppression System for Obstructed Fire Suppression Scenarios on Naval Vessels" project was initiated as part of the “Civil-Military Technology Practical Implementation Collaboration Project” to advance and commercialize the aforementioned autonomous rapid initial fire suppression system. The research period is two years (July 2023 to June 2025), with a total budget of KRW 30 billion invested. A group of five organizations, including the Korea Institute of Civil Engineering and Building Technology (KICT), Korea Institute of Machinery & Materials (KIMM), Super Century Co., Ltd., Chungnam National University (CNU), and Korea Military Academy (KMA), have jointly initiated the research. The primary objective of this project is to strengthen the technological aspects of the autonomous rapid initial fire suppression technology, such as obstructed fire suppression scenario detection, fire extinguishing, enhanced environmental resistance, and aiming performance under maritime conditions. The initial goal is to validate the system's performance through system-linking testing in a simulated naval vessel hangar environment, and the ultimate goal is to install it and conduct field testing on actual naval ships. Unlike the typical practical implementation seen in general projects, this civil-military endeavor is unique in that its practical implementation is not geared towards the ultimate goal of market deployment, but instead targets conducting field tests on the designated naval vessels.
To advance the technology for responding to obstructed fire suppression scenarios, a LiDAR (Light Detection and Ranging) system has been added to the existing 3-channel (RGB/IR/UV) method to enhance fire detection accuracy. The accuracy for fire and non-fire scenarios will be improved by building a diverse fire data set for obstructed fire suppression scenarios. Furthermore, a fire suppression method using foam spray from afar was incorporated, leveraging obstructed fire suppression technology. The extinguishing range has been extended from the current range of 10 m to 24 m, and fires have been classified as open or obstructed depending on the presence of obstacles. In the primary targeted space, the hangar, the main items stored, such as aircraft or helicopters, can become obstacles during fire detection and extinguishing activities, and as such, have been classified as key items for evaluating fire suppression performance. Considering that ships are required to operate flawlessly even during combat, reasonable environmental resistance targets have been established for the fire suppression monitor and analysis and control devices. Additionally, we will incorporate the fire suppression monitor and the freedom of movement for the seat of the fire to ensure precise aiming performance under maritime conditions that is comparable to what could be achieved on land.
Obstructed Fire Suppression Performance Guidelines for Foam Fire Extinguishing Technology
Foam extinguishing technology is generally used for extinguishing fires involving flammable liquids, or fires where water-based fire suppression methods are ineffective or create the risk of fire escalation. The requirements for installation, maintenance, and safety management are specified in the National Fire Agency's Notices "Fire Safety Standards for Foam Extinguishing Systems (NFTC 105)" and "Fire Safety Performance Standards for Foam Extinguishing Systems (NFPC 105)."
The Notices categorize the relevant equipment based on designated areas, including factories or warehouses storing and handling special inflammables, garages or parking lots, aircraft hangars, generator rooms, and various electrical equipment rooms. These include foam water sprinklers, foam head devices, fixed foam discharge systems, compressed air foam fire extinguishing units, hose reel foam fire extinguishing apparatus, and foam hydrants. In terms of equipment performance, they define the expansion ratio and the floor area by type or protection area based on the discharge volume, but do not incorporate the aspect of extinguishing performance.
The fire suppression performance of foam fire extinguishing agents is validated through fire suppression performance tests specified in "ISO 7203-1, Fire extinguishing media-Foam concentrates" and "KS B ISO 7203-1, Firefighting-fire extinguishing agents- Foam concentrates -Part 1: Specification for low-expansion foam concentrates for top application to water-immiscible liquids." With regard to standards pertaining to ships and naval vessels, the Ministry of Oceans and Fisheries (MOF) Notice on "Guidelines for Firefighting Equipment on Ships" covers overall aspects of fixed low-expansion and high-expansion foam fire suppression systems. However, it lacks guidelines for validating their effectiveness in extinguishing fires. This is because it is analyzed that, as with cases on land, the performance testing criteria for fire extinguishing agents are separately addressed in "IMO MSC1/Circ.1312, Revised Guidelines for The Performance and Testing Criteria, and Surveys of Foam Concentrates for Fixed Fire-Extinguishing Systems" by the International Maritime Organization (IMO). The guidelines provide specific standards for the fuel to use, initial conditions (temperature and wind speed), circular fire model specifications, test procedures, and criteria for assessing fire suppression performance. Furthermore, as the "ISO 7203-1" and "KS B ISO 7203-1" guidelines applied on land are identical to "IMO MSC1/Circ.1312" for maritime use, this project aims to establish procedures for validating the fire suppression performance of foam spraying from a distance by referring to the guidelines of the International Maritime Organization's "IMO MSC1/Circ.1312," which are most relevant.
Establishment of Fire Suppression Performance Validation Procedures for Autonomous Fire Suppression Systems in Naval Vessels in Response to Fuel Fires
Foam fire extinguishing functionality has been integrated into the existing autonomous rapid initial fire suppression system in order to effectively address fuel fires. Additionally, a procedural plan has been devised to evaluate and validate its performance, ensuring that the system meets the designated performance objectives upon practical implementation. The aim is to establish the overall details of the fire extinguishing performance validation procedure at this initial stage of the project. Subsequently, iterative fire suppression tests will be carried out in the hangar model of naval vessels to glean specific insights for further details. The environmental conditions for validating the fire extinguishing performance were aligned with the guidelines outlined in "IMO MSC1/Circ.1312" regarding performance tests for fire, as mentioned earlier. Furthermore, considering the nature of the fire suppression system intended for development in this project, additional details based on environmental conditions were considered, taking into account requirements such as long-range spraying. Considering the special features of naval vessels (large space, carrier-borne aircraft, and helicopter operations), clear fire suppression performance and test procedures were presented to enable an effective response in the event of a fuel fire.
| Performance Validation Test Location and Initial Conditions | - Initial Conditions: Surrounding temperature of 15±5℃, fuel temperature of 17.5±2.5℃, water temperature of 17.5±2.5℃, foam solution temperature of 17.5±2.5℃, maximum wind speed (near the test model) 3 m/s
- Fuel for the seat of fire: n-heptane |
| Open Fire Suppression Scenario | - Definition: Conditions in which there are no obstacles between the targeted seat of fire (fire model) and the foam fire suppression monitor - Seat of fire (circular fire model): Inner diameter from edge (2,400±25 mm), depth of 200±15 mm, nominal thickness of steel plate (2.5 mm): Area 4.52 m²
- Performance Validation Test Procedure for Open Fire Suppression Scenario
① Position the circular fire model at a target distance of 20 m in the wind direction of the fire suppression monitor.
② Fill the circular fire model with approximately 90 L of fresh water and confirm that the model's bottom is completely covered with water.
③ Inject n-Heptane capable of burning for 7 minutes or more into the 4.5 m² circular fire model.
④ Ignite the circular fire model within 5 minutes after adding the fuel.
⑤ Activate the autonomous foam fire suppression system for rapid initial fire suppression 10 seconds after ignition.
⑥ Measure the extinguishing time from the start of foam discharge by monitor operation following fire detection.
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| Obstructed Fire Suppression Scenario | - Definition: Conditions in which there is an obstacle between the targeted seat of fire (fire model) and the foam fire suppression monitor (a helicopter model will be positioned above the seat of fire as an obstacle).
- Seat of fire (quadrangular fire model): Area of 3.0 m² (apart from the area, same conditions as those of open fires)
- Performance Validation Test Procedure for Obstructed Fire Suppression Scenario
① Position the circular fire model at a targeted distance of 20 m in the wind direction of the fire suppression monitor.
② Fill the circular fire model with approximately 90 L of fresh water and confirm that the model's bottom is completely covered with water.
③ Inject n-Heptane capable of burning for 7 minutes or more into the 3.0 m² circular fire model.
④ Ignite the circular fire model within 5 minutes after adding the fuel.
⑤ Activate the autonomous suppression system for rapid initial fire suppression 10 seconds after ignition.
⑥ Measure the extinguishing time from the start of foam discharge by monitor operation following fire detection. |
| Fire Suppression Performance Assessment Criteria | Complete extinguishment within 5 minutes denotes success (Extinguishment time is defined as the time from the start of foam discharge to the moment when all flames within the seat of fire are completely extinguished, with flame presence assessed visually.)
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Epilogue
Over the past three years, through research aimed at effectively responding to fires occurring in naval vessels, we have successfully developed the autonomous rapid initial fire suppression system. This achievement has confirmed the potential for Korea’s global leadership and advancement in automated fire suppression technology. Moving forward, through subsequent practical application projects, we aim to enhance long-range response capabilities for fuel fires and validate the utility of such methods by applying them to actual naval vessels or ships. Furthermore, beyond naval vessels, we anticipate advancing into the future core technologies of fire and disaster prevention in the firefighting/protection and disaster prevention fields, in key areas related to modern industrial transformations, such as deep spaces and EV battery fires.
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References
• Korea Institute of Machinery & Materials (2023), Development of autonomous fire suppression system for rapid initial suppression of fuel fires on naval vessels. Research and Development Plan.
• Park Jin-ouk, Yoo Yong-ho, Kim Hwi-sung, Jeon Gil-song, Yoo Jeong-hoon (2023), Study on the establishment of performance validation procedures for autonomous fire suppression systems for rapid initial suppression of fuel fires on naval vessels. Proceedings of the 2023 Autumn Academic Conference of the Korean Association for Fire Science and Engineering, pp. 148.
• KS B ISO 7203-1(2019), Firefighting-fire extinguishing agents- Foam concentrates -Part 1: Specification for low-expansion foam concentrates for top application to water-immiscible liquids
• ISO 7203-1(2019), Fire extinguishing media - Foam concentrates-Part 1: Specification for low-expansion foam concentrates for top application to water-immiscible liquids
• International Maritime Organization (2009), Revised Guidelines for The Performance and Testing Criteria, and Surveys of Foam Concentrates for Fixed Fire-Extinguishing Systems
